AIR-QUALITY MONITORING AT INDORE CITY WITH SPECIAL REFERENCE TO SO2 AND TREE BARK PH

Ambient SO2 concentrations were computed on the basis of sulphation ra te at twelve sampling stations for successive three years. Maximum SO2 concentration was noted at Pardeshipura, predominantly an industrial area. The bark of the trees growing in polluted areas showed increased acidic nature, which corresponds to the concentrations of SO2 in air. A maximum change in bark pH was recorded in E. jambolana while Eucaly ptus species remained least affected.